Staple-optional insulation batt for friction-fit and/or stapling applications, and corresponding methods

ABSTRACT

An insulation batt with vapor retarder is adapted to be friction-fit installed in cavities such as vertically extending wall cavities. The batt is adapted to be installed differently in closed cavities compared to open cavities. In certain example embodiments, stapling flanges or tabs are provided on a friction-fit batt so that (a) in closed cavity applications, the batt can be friction-fit installed in a closed cavity without the need for stapling, and (b) in open cavity applications, the same batt can be friction-fit installed and additionally stapled to the studs to significantly improve the batt&#39;s ability to withstand environmental conditions without falling out of the cavity.

This invention relates to an insulation batt (e.g., with fiberglass insulation) sized for friction-fitting between adjacent wall studs, and which also includes tabs for stapling-type application in open wall cavities or the like. This invention also relates to a method of installing such an insulation batt in a friction-fit manner in a closed wall cavity and/or in a stapling manner in an open wall cavity or the like.

BACKGROUND OF THE INVENTION

Insulation batts are known for use in insulating wall cavities in homes and the like. An insulation batt typically includes a layer of insulation (e.g., fiberglass insulation), one side of which is adhered to a vapor retarder such as kraft paper.

Generally speaking, in homes under construction there are two different types of vertically extending wall cavities to be insulated, namely closed cavities and open cavities. A closed cavity to be insulated has one of its two major sides closed at the time of insulation as a type of backing, whereas an open cavity has its two major sides open at the time of insulation. Note that the “major” sides of such cavities are not the sides closed off by studs, but instead are the major sides typically covered by siding, brick, and/or drywall.

FIGS. 1(a) and 1(b) illustrate example differences between closed cavities (see FIG. 1(a)) and open cavities (see FIG. 1(b)). Closed cavities are typically found on exterior walls of houses (i.e., walls which are adjacent the home's exterior).

As shown in FIG. 1(a), at the time insulation is applied, a closed cavity 2 has one of its two major surfaces closed off by walling material 3 such as brick, siding and/or drywall. The left and right minor sides of the vertically extending cavity are defined by vertically extending studs 4. The top and bottom minor sides (not shown) of the cavity may be defined by a ceiling, floor, cross-ways oriented stud, and/or the like although this is not shown in the figure for purposes of simplicity. Studs 4 are typically wood two-by-fours, although other types of studs may also be used. Typically, the rear major side of the vertically extending cavity is closed off in such a manner by walling material 3. Most often, since walls are typically insulated before drywall is applied, closed cavities have their major rear sides closed off with brick or siding, as opposed to drywall.

Still referring to FIG. 1(a), an insulation batt(s) is inserted into the closed cavity of FIG. 1(a) through the open front major side thereof, and the rear side walling material 3 (typically brick or siding) supports the rear surface of the batt and prevents the insulation batt from going through the cavity. After the batt has been inserted into the cavity 2, the front major side of the cavity is closed off as drywall or the like is affixed to the front surfaces of studs 4.

In contrast with a closed cavity, an open cavity 6 has both of its major sides (i.e., the front and rear major sides) open at the time of insulation installation as shown in FIG. 1(b). Open cavities are typically found in homes under construction in locations such as between a kitchen and a garage, where neither the front nor rear major side of the cavity is closed off with brick or siding. Other examples of open cavities include interior wall cavities between rooms (e.g., wall between a bathroom or utility room, and another room, desired to be insulated for sound and/or thermal control). Again, since insulation is typically installed prior to drywall installation, such vertically extending cavities 6 are insulated with both the rear and front major sides thereof open. The left and right minor sides of the cavity 6 are defined by vertically extending studs 4. The top and bottom minor sides (not shown) of the cavity 6 may be defined by a ceiling, floor, cross-ways oriented stud, and/or the like although this is not shown in the figure for purposes of simplicity. Studs 4 are typically wood two-by-fours, although other types of studs may also be used.

Given an open cavity as shown in FIG. 1(b), an insulation batt is typically installed therein with both major sides of the cavity being open, and thereafter drywall or the like is applied to the front and rear sides of the studs 4 to close off the cavity.

In the past, insulation batts have typically been sized so as to easily fit within the cavity. In particular, batts have been sized to have widths slightly smaller than widths of intended cavities, so that when installed into such cavities stapling flanges along the edges of such batts have been used to locate the batts in their corresponding cavities. However, those in the art have felt that stapling flanges are undesirable since they are labor intensive during the installation process.

Recently, friction-fit fiberglass tabless insulation batts 8 have been introduced to the marketplace (e.g., see FIG. 2) in order to eliminate the need for stapling and stapling flanges. Friction-fit batts 8 include a layer of fiberglass insulation 9 to one side of which kraft paper 10 is adhered in a known manner. Examples of such batts are sold commercially under the following tradenames: “SpeedyR Tabless Batts”, available from CertainTeed; “Knauf Staple-Free Insulation”, available from Knauf; and “ProPINK FastBatt”, available from Owens Corning.

Friction-fit batts are sized (in particular, oversized) so as to fit into vertically extending wall cavities without stapling. For example, given a cavity width of 14½ inches between adjacent vertically extending studs, a SpeedyR Tabless Batt having a width of 15¼ inches, length of 93 inches and thickness of 3½ inches is used. The oversized batt (e.g., see FIG. 2) is pressed into the cavity, and during such pressing into the cavity the batt deforms since the width of the cavity is smaller than the original width of the oversized batt. However, since such batts are compressible, the oversized batt can be pressed into the cavity while batt deformation occurs. Once in the cavity, the deformed batt biases itself laterally against the vertically extending studs thereby achieving a friction-fit position in the cavity. Due to the friction-fitting of the oversized batt in the cavity, friction-fit batts are not provided with stapling flanges or tabs.

Unfortunately, conventional oversized or friction-fit batts such as SpeedyR Tabless Batts, Knauf Staple-Free Insulation, and ProPINK FastBatt are problematic at least with respect to open wall cavities to be insulated. While such friction-fit batts can be installed into vertically extending open wall cavities such as that shown in FIG. 2, the friction-fit of the batt is not particularly strong. Thus, such batts often end up blowing out of such open cavities when the wind blows before the drywall can be installed to help hold the insulation in place, thereby requiring an insulation contractor to again re-install the open cavities typically with new insulation (wind is not particularly problematic for closed cavities since one major side of such cavities is closed by brick, siding or the like). As will be appreciated by those skilled in the art, this is very problematic and can result in significant increases in labor, cost, materials and overall burdens. Another problem which can result from such friction-fit batts' tendency to blow out of open cavities is that drywall contractors may arrive and apply the drywall to non-insulated open cavities (which friction-fit batts have blown out of) thereby resulting in a home with insufficient insulation.

In view of the above, there exists a need in the art to improve the ability to maintain friction-fit batts in position in open wall cavities once installed therein. It would be desirable if an insulation batt could be provided which could be friction-fit installed in both open and closed type cavities in respective manners such that (a) mere blowing of the wind would not cause such batts to fall out of open cavities, (b) stapling could be avoided in closed cavities; and/or (c) removal from closed cavities could be made easier so that such batts could be easily removed from closed cavities without significant risk of destroying the batt(s).

BRIEF SUMMARY OF EXAMPLES OF THE INVENTION

In certain example embodiments of this invention, there is provided an insulation batt adapted to be friction-fit installed in cavities such as vertically extending wall cavities. The batt is adapted to be installed differently in closed cavities compared to open cavities. In certain example embodiments, stapling flanges or tabs are provided on a friction-fit batt so that (a) in closed cavity applications, the batt can be friction-fit installed in a closed cavity without the need for stapling, and (b) in open cavity applications, the same batt can be friction-fit installed and additionally stapled to the studs to significantly improve the batt's ability to withstand environmental conditions (e.g., wind blowing) without falling out of the cavity.

This is advantageous in that it permits a single batt type to be used which can take advantage of friction-fit installation without stapling in closed cavity situations, but where the batt is much less susceptible to the falling out problems discussed above in open cavity situations. Moreover, the provision of the flanges or tabs have also been surprisingly found to improve the ability of such batts to maintain their friction-fit position in closed cavities, since the batt can be arranged in a manner that permits the flange(s) or tab(s) to bias against an adjacent stud during friction-fitting of the batt in the cavity.

In certain example embodiments of this invention, the method of installation for the batt is based on whether the vertically extending wall cavity into which the batt is to be installed in of the open or closed type. An installer makes a determination as to how the batt is to be installed based on the answer to this question of whether the cavity is of the open or closed type.

In certain example embodiments of this invention, there is provided a method of installing a friction-fit batt into a vertically extending wall cavity, the method comprising: providing an insulation batt including a vapor retarder adhered to insulation comprising fiberglass, wherein the vapor retarder includes flexible flanges provided at edge portions thereof which are flexible relative to a major portion of the vapor retarder, the insulation batt having a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt; determining whether the friction-fit type batt is to be installed in a closed cavity or an open cavity; when it is determined that the friction-fit batt is to be installed in a closed cavity, then pressing the batt into the closed cavity in a friction-fit manner without stapling the flanges to studs which at least partially define the closed cavity; and when it is determined that the friction-fit batt is to be installed in an open cavity, then pressing the batt into the open cavity in a friction-fit manner and stapling the flanges to studs which at least partially define the open cavity.

In other example embodiments of this invention, there is provided a friction-fit insulation batt comprising: an insulation layer comprising fiberglass; a vapor retarder adhered to the insulation layer comprising fiberglass, wherein the vapor retarder includes flexible flanges provided at edge portions thereof which are flexible relative to a major portion of the vapor retarder; and wherein the insulation batt has a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1(a) is a side plan view illustrating an example vertically extending wall cavity which is of the closed type.

FIG. 1(b) is a side plan view illustrating an example vertically extending wall cavity which is of the open type.

FIG. 2 is a cross sectional view of a conventional friction-fit fiberglass insulation batt.

FIG. 3 is a cross sectional view of a vapor retarder (e.g., kraft paper) to be used on a friction-fit batt according to an example embodiment of this invention.

FIG. 4 is a cross sectional view of a friction-fit insulation batt, including the vapor retarder of FIG. 3, according to an example embodiment of this invention.

FIG. 5 is a top (or bottom) cross sectional view illustrating the friction-fit batt of FIG. 4 friction-fit in a closed wall cavity according to an example embodiment of this invention.

FIG. 6 is a top (or bottom) cross sectional view illustrating the friction-fit batt of FIG. 4 friction-fit in an open wall cavity according to an example embodiment of this invention.

FIG. 7 is a flowchart illustrating certain example steps performed during a method of insulation installation according to an example embodiment of this invention.

DETAILED DESCRIPTION OF EXAMPLES OF THE INVENTION

Referring now to the particular drawings in which like reference numerals indicate like parts throughout the several views.

FIG. 4 is a cross sectional view of an insulation batt 11 according to an example embodiment of this invention, the batt 11 including for example fiberglass insulation 9 and a vapor retarder such as kraft paper 12. The vapor retarder 12 is adhered to the insulation 9 in any suitable manner such as with a polymer adhesive and/or asphalt based adhesive (not shown). While the vapor retarder 12 is shown in FIG. 4 as being adhered to only one major surface of the insulation 9, it is also possible to apply vapor retarder to both sides of the insulation in alternative embodiments of this invention. It is noted that vapor retarder 12 may be of a material other than kraft paper in alternative embodiments of this invention, including both not limited to another type of paper or other suitable material. Meanwhile, other materials may be used as the insulation 9 in alternative embodiments of this invention. FIG. 3 is a cross sectional view of the vapor retarder 12 (e.g., kraft paper) used in the batt 11 of FIG. 4.

In certain example embodiments of this invention, the batt 11 in order to permit friction-fitting to be possible, has a width of at least about 15 inches, more preferably of at least 15¼ inches, and possibly at least 15½ inches. Most preferably, the batt 11 has a width of from about 15 to 15¾ inches, more preferably from about 15¼ to 15¾ inches. These widths permit friction-fitting in normal sized vertically extending wall cavities. Other sizes of friction-fitting batts 11 may also be used (e.g., for 24 inch on center studs (e.g., batt width of from about 23¼ to 23¾ inches for friction-fitting).

Moreover, vapor retarder 12 preferably has a width (not including the flexible portions of the tabs 20) which is less than that of the fiberglass insulation 9. In certain example embodiments, the edge of the vapor retarder 12 is laterally offset from the edge of the insulation 9 by a distance “d” one or both edge portions of the batt as shown in FIG. 4. In certain example embodiments, offset “d” is from about ⅛ to ½ inches, more preferably from about ⅛ to ¼ inches. Accordingly, in certain example embodiments, the vapor retarder 12 may have an overall width (not including the flexible portions of tabs 20) of about 14⅞ inches or less. This is highly advantageous in that it permits the same vapor retarder 12 to be used in connection with both friction fit batts 11 according to certain example embodiments of this invention, as well as conventional non-friction-fit batts.

FIG. 5 is a top (or bottom) cross sectional view (as viewed from the ceiling or floor for example) illustrating the friction-fit batt 11 of FIG. 4 friction-fit in a vertically extending closed wall cavity 2 according to an example embodiment of this invention, whereas FIG. 6 is a top (or bottom) cross sectional view illustrating the same friction-fit batt 11 of FIG. 4 friction-fit in a vertically extending open wall cavity 6 according to an example embodiment of this invention. FIGS. 5 and 6 are to be compared to one another, and illustrate that the same batt 11 is installed differently depending upon whether the cavity is of the closed type 9 (FIG. 5) or the open type (FIG. 6).

As explained above with respect to FIGS. 1(a) and 1(b), open and closed vertically extending cavities have very different features. Closed cavities (e.g., see FIG. 1(a)) are typically found on exterior walls of houses (i.e., walls which are adjacent the home's exterior), whereas open cavities (e.g., see FIG. 1(b)) typically are not.

As for a closed cavity 2 as shown in FIGS. 1(a) and 5, at the time insulation is applied, a closed cavity 2 has one of its two major surfaces closed off by walling material 3 such as brick, siding, or the like. The left and right minor sides of the vertically extending cavity are defined by vertically extending studs 4. Studs 4 are typically wood two-by-fours, although other types of studs may also be used. Insulation batt(s) 11 is inserted into the closed cavity through the open front major side thereof, and the rear side walling material 3 (typically brick or siding) supports the rear surface of the batt 11 and prevents the insulation batt from going through the cavity as shown in FIG. 5. After the batt 11 has been inserted into the cavity 2 as shown in FIG. 5, the front major side of the cavity is closed off as drywall or the like is affixed to the front surfaces 4 a of studs 4.

In contrast with a closed cavity, an open cavity 6 has both of its major sides (i.e., the front and rear major sides) open at the time of insulation installation as shown in FIGS. 1(b) and 6. Open cavities are typically found in homes under construction in locations such as between a kitchen and a garage, where neither the front nor rear major side of the cavity is closed off with brick or siding 3. In other words, the open cavity 6 of FIG. 6 (and FIG. 1(b)) is the same as the closed cavity 2 of FIG. 5 (and FIG. 1(a)), except that the walling material 3 is not present in the open cavity 6 at the time of insulation installation.

Referring to FIGS. 3-6, insulation batt 11 is adapted to be friction-fit installed in cavities such as vertically extending wall cavities 2 and 6. The batt 11 is adapted to be installed differently in closed cavities 2 compared to open cavities 6. In certain example embodiments, the vapor retarder 12 of the batt 11 is provided with flanges or tabs 20 at edge portions thereof. The flanges or tabs 20 may, for example, be originally formed by double-folding the edge portions of the vapor retarder 12 (e.g., kraft paper) as shown in FIG. 3. Then, an adhesive (asphalt based adhesive and/or polymer based adhesive) is provided in gap 22 to adhere the upper and intermediate fold portions to one another (see FIG. 3). Thereafter, the flange or tab 20 (made up of two layers of vapor retarder adhere to each other) is provided so as to be bendable in directions 24 about respective axes 26 defined at the respective edges of the retarder 12.

The provision of flanges or tabs 20 is advantageous for a number of reasons. For example, in closed cavity applications such as shown in FIG. 5, the batt 11 can be friction-fit installed in a closed cavity 2 without the need for stapling. However, in open cavity applications, the same batt 11 can be friction-fit installed and additionally stapled to the studs 4 to significantly improve the batt's ability to withstand environmental conditions (e.g., wind blowing) without falling out of the cavity as shown in FIG. 6. This is advantageous in that it permits a single batt type 11 to be used which can take advantage of friction-fit installation without stapling in closed cavity situations (FIG. 5), but where the batt is much less susceptible to the falling out problems discussed above in open cavity situations (FIG. 6). In different embodiments of this invention, the stapling can be performed in different manners. For example, inset stapling occurs where the flange or tab 20 is stapled to a side major surface of the stud as opposed to the outer face of the stud 4. As another example, face stapling occurs were the flange or tab 20 is stapled to the outer face 4 a of the stud. Inset stapling is preferred in many instances because it interferes less with drywall applications following insulation installation.

Moreover, the provision of the flanges or tabs 20 has also been surprisingly found to improve the ability of such batts to maintain their friction-fit position in closed cavities 2, since the batt 11 can be arranged in a manner that permits the flange(s) or tab(s) 20 to fit against an adjacent stud(s) 4 during friction-fitting of the batt in the cavity as shown in FIG. 5. In other words, as shown in FIG. 5, a flange or tab 20 can be tucked into the side edge of the cavity 2 so that a bottom surface 26 of the flange or tab 20 contacts the stud 4 thereby improving the friction-fitting of the batt 11 in the closed cavity 2. It has also been found that tabs 20 enable the removal of the batt 11 from a closed cavity to be easier without the risk of significant damage or destruction of the batt during removal from the cavity, in that a user can simply grab loose tabs 20 and use them to pull the batt from the closed cavity 2 without destroying the batt in the process.

The phrase “friction fit” is explained as follows. Friction-fit batts 11 are sized (in particular, oversized) so as to fit into vertically extending wall cavities so that at least biasing force of the batt against the studs after installation is capable of retaining the batt in the cavity. For example, given a cavity width of 14½ inches between adjacent vertically extending studs 4, a friction fit batt 11 can be provided with an example width of 15¼ inches, length of 93 inches and thickness of 3½ inches is used (i.e., the width of the batt 11 is greater than that of the cavity into which the batt is to be installed). The oversized batt 11 is pressed into the cavity (2 or 6), and during such pressing into the cavity the batt 11 deforms since the width of the cavity is smaller than the original width of the oversized batt 11. Since such batts are compressible, the oversized batt can be pressed into the cavity while batt deformation occurs. Once in the cavity, the deformed batt 11 biases itself laterally against the vertically extending studs 4 as shown in FIGS. 5 and 6 thereby achieving a friction-fit position in the cavity.

FIG. 6 illustrates how batt 11 can be installed into an open cavity 6. In FIG. 6, the batt 11 is friction-fit into the open cavity 6 since the width of the cavity is smaller than the original width of the batt 11 as discussed above. However, due to the open cavity problems discussed herein, the flanges or tabs 20 of the batt 11 are used in open cavity applications to affix the batt to the studs 4. In particular, staples 30 are used so as to penetrate the flanges or tabs 20 and extend into the studs 4 thereby affixing the vapor retarder 12 and thus the batt 1 to the studs 4. This prevents the batt 11 from being blown out of the open cavity 6 on windy days for example, prior to drywall installation.

In certain example embodiments of this invention, the method of installation for the batt 11 is based on whether the vertically extending wall cavity into which the batt is to be installed in of the open or closed type. An installer makes a determination as to how the batt is to be installed based on the answer to this question of whether the cavity is of the open or closed type.

FIG. 7 illustrates an example flowchart showing steps performed during installation of batts 11 according to an example embodiment of this invention. First, a friction-fit batt 11 (e.g., see FIG. 4) is provided (S1). An installer then makes a determination whether the batt 11 is to be installed in a closed vertically extending cavity 2 or an open vertically extending cavity 6 (S2). If the batt 11 is to be installed in a closed cavity, then the installer friction-fit installs the batt 11 into the closed cavity 2 as shown in FIG. 5 without stapling of the tabs (S3). While the tabs 20 in FIG. 5 are shown tucked into the side of the cavity, this invention is not so limited as it is possible that even in closed cavity applications the tabs 20 may extend over the front faces 4 a of the studs in an overlapping manner without stapling. After the batt has been installed in the closed cavity, the cavity 2 is ultimately closed by applying drywall of the like thereover (S4). For example, drywall may be affixed to the front faces 4 a of the studs 4 in a known manner.

However, still referring to FIG. 7, if the batt 11 is to be installed in an open cavity, then the installer friction-fit installs the batt 11 into the open cavity 6 (see FIG. 6) (S5). Then, the installer staples the flanges or tabs 20 to the front faces of the studs 4 as shown in FIG. 6 (S6). After the batt 11 has been installed in the open cavity 6, the cavity is ultimately closed by applying drywall of the like thereover (S7). For example, drywall may be affixed to the front faces of the studs 4 in a known manner.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 

1. A method of installing a friction-fit batt into a vertically extending wall cavity, the method comprising: providing an insulation batt including a vapor retarder adhered to insulation comprising fiberglass, wherein the vapor retarder includes flexible flanges provided at edge portions thereof which are flexible relative to a major portion of the vapor retarder, the insulation batt having a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt; determining whether the friction-fit type batt is to be installed in a closed cavity or an open cavity; when it is determined that the friction-fit batt is to be installed in a closed cavity, then pressing the batt into the closed cavity in a friction-fit manner without stapling the flanges to studs which at least partially define the closed cavity; and when it is determined that the friction-fit batt is to be installed in an open cavity, then pressing the batt into the open cavity in a friction-fit manner and stapling the flanges to studs which at least partially define the open cavity.
 2. The method of claim 1, wherein the vapor retarder comprises paper.
 3. The method of claim 2, wherein the vapor retarder has a width which is less than a width of the insulation of the batt.
 4. The method of claim 3, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation by a distance “d”, wherein distance “d” is from about ⅛ to ½ inches.
 5. The method of claim 4, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation by a distance “d”, wherein distance “d” is from about ¼ to ½ inches.
 6. The method of claim 4, wherein the paper has a width of about 14⅞ inches, not including the flanges thereof.
 7. The method of claim 1, wherein when the batt is installed in the closed cavity, tucking at least part of at least one of the flanges into an edge of the cavity so that what is normally an outer surface of the flange contacts an adjacent stud.
 8. The method of claim 1, wherein the vapor retarder comprises paper, and wherein each of the flanges uses multiple overlapping portions of the paper so as to be thicker and more durable than a major portion of the vapor retarder which uses only a single layer of the paper.
 9. A method of installing a friction-fit batt into a vertically extending open wall cavity, the method comprising: providing an insulation batt including a vapor retarder adhered to insulation comprising fiberglass, wherein the vapor retarder includes flanges provided at edge portions thereof, the insulation batt having a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt; and pressing the batt into the open cavity in a friction-fit manner and stapling the flanges to studs which at least partially define the open cavity.
 10. The method of claim 9, wherein the vapor retarder comprises paper.
 11. The method of claim 10, wherein the vapor retarder has a width which is less than a width of the insulation of the batt.
 12. The method of claim 11, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation by a distance “d”, wherein distance “d” is from about ⅛ to ½ inches.
 13. The method of claim 12, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation by a distance “d”, wherein distance “d” is from about ¼ to ½ inches.
 14. The method of claim 12, wherein the paper has a width of about 14⅞ inches, not including the flanges thereof.
 15. The method of claim 9, wherein the vapor retarder comprises paper, and wherein each of the flanges uses multiple overlapping portions of the paper so as to be thicker and more durable than a major portion of the vapor retarder which uses only a single layer of the paper.
 16. A method of installing a friction-fit batt into a closed wall cavity, the method comprising: providing an insulation batt including a vapor retarder adhered to insulation comprising fiberglass, wherein the vapor retarder includes flexible flanges provided at edge portions thereof which are flexible relative to a major portion of the vapor retarder, the insulation batt having a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt; pressing the batt into the closed cavity in a friction-fit manner without stapling the flanges to studs which at least partially define the closed cavity.
 17. The method of claim 16, further comprising locating at least part of at least one of the flanges in an edge portion of the cavity so that what is normally an outer surface of the flange contacts an adjacent stud.
 18. A friction-fit insulation batt comprising: an insulation layer comprising fiberglass; a vapor retarder adhered to the insulation layer comprising fiberglass, wherein the vapor retarder includes flexible flanges provided at edge portions thereof which are flexible relative to a major portion of the vapor retarder; and wherein the insulation batt has a width of from about 15¼ to 15¾ inches so as to be a friction-fit type batt.
 19. The batt of claim 18, wherein the vapor retarder comprises paper.
 20. The batt of claim 19, wherein the vapor retarder has a width which is less than a width of the insulation layer.
 21. The batt of claim 20, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation layer by a distance “d”, wherein distance “d” is from about ⅛ to ½ inches.
 22. The batt of claim 21, wherein an edge of the paper is laterally offset from an adjacent edge of the insulation layer by a distance “d”, wherein distance “d” is from about ¼ to ½ inches.
 23. The batt of claim 21, wherein the paper has a width of about 14⅞ inches, not including the flanges thereof.
 24. The batt of claim 18, wherein the vapor retarder comprises paper, and wherein each of the flanges uses multiple overlapping portions of the paper so as to be thicker and more durable than a major portion of the vapor retarder which uses only a single layer of the paper. 